1. Field of the Invention
The present invention relates to protective breathing devices, and, more particularly, to a chemical and biological protection mask that combines a filter cartridge with a miniaturized high-intensity shortwave UV disinfecting system.
2. Description of the Background
There is a wide variety of prior art with regard to gas masks and breathing gas respirators. Most conventional gas mask/respirators utilize a half-mask or full face mask that covers the nose and mouth and in the latter case the entire upper face.
Gas masks as described above use a face piece made of an impermeable material, resistant to chemical agents and a harness which allows the mask to be put on the user's head so as to provide a tight seal between the edges of the face piece and the user's face. Once the mask is put on, the user can inhale air from the outside through an inflow opening arranged on the face piece and provided with a threaded or twist-lock fitting. A filtering cartridge is inserted onto the fitting to decontaminate the air being inhaled. The air subsequently exhaled by the user is expelled from the mask through an outflow opening, also arranged on the face piece and provided with a one-way valve. The face piece comprises two eye-pieces or, alternatively, a single transparent screen to give the user full visibility.
Conventional gas mask/respirators invariably utilize a cartridge containing various filter media. In their simplest form, the cartridges incorporate a filter cloth, charcoal, or polymeric material that merely filters out particulate materials including sprays and colloidal suspensions. Those filters that rely on activated charcoal eliminate particulate material and also adsorb vapor and gas contaminants as they come in contact with the charcoal. The most effective filtration media is a HEPA-type filter formed of pleated filter paper with minute interstices for allowing the passage of air there through.
Despite their effectiveness against particulate materials and suspensions, the foregoing and other known filter-type gas masks are not sufficiently effective in filtering biological organisms such as viruses and germs. With the increased threat of biological warfare, there is currently a significant need for a gas mask/respirator capable of killing germs as well as filtering toxins.
In other application, chemical agents are often used to destroy or kill germs and bacteria. However, it particularly difficult to incorporate chemical mechanisms into a gas mask.
UV radiation is another known germicide. Germicidal ultraviolet (UVC) light kills cells by damaging their DNA. Ultraviolet photons harm the DNA molecules of living organisms, and the distorted DNA molecules do not function properly, cannot replicate, and eventually the cells die. High-intensity shortwave ultraviolet light is commonly used for disinfecting smooth surfaces such as dental tools, and ultraviolet light fixtures are often present in labs. Unfortunately, existing UV-light sources for biocidal applications are typically fluorescent UV light bulbs. These bulbs are large and require the presence of a ballast and AC power source for stable operation. The size requirements of high-intensity shortwave ultraviolet disinfectant systems are unsuitable for portable use in any gas mask, and so these systems are not known in this context.
There would be great advantage in a breathing gas mask or respirator that combines a filter cartridge with a miniaturized high-intensity shortwave UV disinfecting system, in a compact easy-to-wear and fully portable form factor.